1. Field of the Invention
The present invention relates, generally, to ultrasonic transducer probes, more especially to continuous wave ultrasonic transducer probes, and most particularly to such a transducer probe for medical diagnostic procedures wherein the probe is positioned within the suprasternal notch of a human patient in order to insonify the ascending aorta.
2. Description of the Background Art
Insonification of mammalian organs as a medical diagnostic technique has come to the fore within the last decade. Ultrasonic energy is transmitted into a body and reflected energy from object organs, tissues, or the like within an insonified region or field is received, processed, thence analyzed as an indication of extant conditions thereof. Ultrasonic diagnostic procedures are now relatively commonplace in the examination of human patients to identify a wide range of physical conditions and/or disorders; ranging, e.g., from prenatal examinations of a fetus to the measurement of cardiac output. As will be appreciated more fully as this description ensues, it is to devices for use within the latter class that the invention is most particularly related.
Substantial attention has been paid in the art of ultrasonic diagostics to improvements in the systems employed for generating and receiving the ultrasonic energy and methods and means for analysis of the results obtained thereby. Only scant attention has been paid to the design of the transducer probe utilized in conjunction with these systems. For those systems destined for examination, e.g., of prenatal conditions where the ultrasonic transducer is applied to the abdominal region of a patient, there are very few limiting geometrical constraints on the size and shape of the transducer probe. Contrariwise, important considerations of patient comfort and operator efficiency obtain in respect of ultrasonic examination via insonification through the suprasternal notch, as is the case where cardiac output is being examined by insonification of the ascending aorta. Within that context, the patient may be in a supine position, perhaps partially elevated, while the system operator places the head of the transducer probe within the suprasternal notch and is required to manipulate that probe in order to effectuate beam steering for the purpose of positioning the transducer elements properly relative to the cardiac region. The transducer head is usually at least partially obscured from view of the operator by virtue of its disposition within the suprasternal notch. Typically, the operator is observing an output device, usually a graphic output such as a CRT, to achieve appropriate positioning of the probe; attention thus diverted from the physical placement of the probe within the notch of the patient under examination. On the other hand, the patient must remain reasonably still while the operator manipulates the probe and, accordingly, patient comfort is a requirement which should not be underestimated lest patient movement in response to discomfort may contribute to erroneous data.
To date, the art has yet to respond to the combined needs for an ultrasonic transducer probe which assists in positioning by the operator without the need for direct visual observation during manipulation while allowing for improved patient comfort during necessary manipulation while the probe is disposed within the suprasternal notch.